Showing papers in "Optics and Lasers in Engineering in 1981"

TL;DR: In this article, the factors affecting the quality of the moire fringes for an arbitrary displacement and deformation of the object surface are analyzed. And the physical significance of speckle displacement, both in the image plane and in the pupil plane, is pointed out.

TL;DR: The study provides evidence that the white light speckle technique is not exclusively sensitive to the in-plane components of displacement, and proposes two complementary techniques which promise to eliminate the influence of the out-of-plane movements on the measurement of the lateral component of displacement.

TL;DR: In this article, an account is given of the technique of image derotated holographic interferometry (IDHI) as applied to the study of the vibrations of rotating components.

TL;DR: In this paper, the mathematical models developed to describe the gas jet laser cutting process are examined and some experimental results for the laser cutting of carbon and stainless steels are also shown.

TL;DR: Using Fizeau interferometry it is possible to study the thickness variations of such oil films with position and time as mentioned in this paper, which can be related to the surface streamline pattern and the skin friction distribution.

TL;DR: In this paper, the acoustic emission signals from the laser surface heating of En8 steel, a stainless steel, 0.25% C mild steel, an α/β brass, and Al-4% Cu were analysed.

TL;DR: The construction and use of an electronic speckle pattern interferometer for vibration testing of critical gas turbine parts in the factory, is described.

TL;DR: A laser shadowgraph/schlieren system was built and flown on KC-135 low gravity simulation flights to observe gravity-related flow arising during solidification of ammonium chloride and water, and growth plumes in the solution were observed and photographed using shadowgraph and schlieren techniques.

TL;DR: In this article, a four-aperture arrangement was introduced for recording white light speckles and the resulting isothetics were better in quality than those obtained by the traditional three-and-one arrangement.

TL;DR: The theory of fringe formation and methods of analysis are found to be well-established, but little experience has been gained in the areas where the scattered-light method has the most potential: three-dimensional thermal, dynamic and elastoplastic stress analysis.

TL;DR: The experimental results show that video techniques are more useful for superimposing two ‘Fourier images’ than photographic techniques.

TL;DR: It will be shown that the computerised interferometers are more suitable for testing than computer-generated synthetic hologram interferometer.

TL;DR: In this paper, a novel form of holocamera was developed by modifying a standard 35 mm reflex camera to take miniature-format volume-reflection holograms, which can be used for time-averaged or frozen-fringe interferometry under ambient lighting conditions without the need for complex vibration isolation.

TL;DR: In this article, the laser light scattering pattern in a wide angle is measured using a system designed and constructed to employ a linear 512 -photodiode array for the morphological investigation of single microscopic particles and biological cells.

TL;DR: In this paper, an aspherical optical system for a rotator to separate compound fringes is proposed, which offers the advantages of large field of view, clearer image, shorter focal length and better utilisation of the laser energy.

TL;DR: Theoretical and experimental results of a thermoplastic acoustic holographic recording device are presented in this paper, which includes the existence of an in-line reference beam and its influence on the real-time coherent optical image reconstruction.